- With just over three weeks of Eskom’s winter outlook period still remaining, the state owned energy utility reports that the system remains well-positioned to maintain stability and meet demand effectively.
As of today, unplanned outages stand at 11 170MW, a significant progress in plant performance as a result of the ongoing implementation of the Generation Recovery Plan, aimed at improving performance and ensuring long-term energy security.
The available generation capacity currently stands at 29 962MW while tonight’s electricity demand is expected to reach 27 878MW. The current capacity is sufficient to meet both today’s demand and anticipated requirements over the weekend.
Respected energy analyst, Chris Yelland confirms that three has been a dramatic improvement in EAF and UCLF this last week to levels very close to the same week in 2024.
The latest Eskom week-on-week energy availability factor EAF for 2025. Data source: Eskom. Image credit: Chris Yelland. Chris is an energy analyst, consultant, electrical engineer, public speaker, writer and MD at EE Business Intelligence (Pty) Ltd. Follow Chris on X – @chrisyelland
During the week of 1 to 7 August 2025, planned maintenance averaged 5 343MW. Over the same period, the Energy Availability Factor (EAF) ranged between 62% and 70%, with the month-to-date average rising to 65.38%, reflecting the fleet’s growing stability and improved reliability. This figure excludes the 720MW from Kusile Unit 6, which has been supplying electricity to the national grid since 23 March 2025, although not in commercial operation.
The latest Eskom week-on-week unplanned capacity loss factor (UCLF) for 2025. Data source: Eskom. Image credit: Chris Yelland. Chris is an energy analyst, consultant, electrical engineer, public speaker, writer and MD at EE Business Intelligence (Pty) Ltd. Follow Chris on X – @chrisyelland
To further strengthen grid stability, Eskom is planning to return a total of 3 280MW of generation capacity to service ahead of the evening peak on Monday, 11 August 2025, and throughout the coming week.
Link to Eskom’s real time performance data portal HERE
Between 1 April and 7 August 2025, the Unplanned Capability Loss Factor (UCLF), which reflects the percentage of generation capacity lost due to unplanned outages, further decreased to 28.35%. This represents a week-on-week improvement of approximately 0.23%, although it remains about 2.3% higher than the 26.06% recorded during the same period last year.
The open-cycle gas turbine (OCGT) load factor reached 5.99% this week, up from the 0.31% recorded during the previous week (25 to 31 July 2025).
From 1 April to 7 August 2025, diesel spend remains within the allocated budget.
The Winter Outlook, published on 5 May 2025, covering the period ending 31 August 2025, remains valid. It indicates that loadshedding will not be necessary if unplanned outages stay below 13 000MW. If outages rise to 15 000MW, loadshedding would be limited to a maximum of 21 days out of 153 days and restricted to Stage 2.
Key Performance Highlights:
- The average total unplanned outages over the past seven days stand at 10 884MW, compared to 10 522MW during the same period last year, a slight increase from the previous week, 362MW higher year-on-year, and 2 116MW below the base case estimate of 13 000MW.
- For the financial year-to-date, planned maintenance has averaged at 5 186MW, representing 11.04% of total generation capacity. This reflects a decrease from the previous week, but a 0.8% increase compared to the same period last year.
- The year-to-date EAF increased to 60.14%, excluding the 720MW contribution from Kusile Unit 6. This figure is below the 63.1% recorded during the same period last year, mainly due to a 2.3% YTD increase in unplanned maintenance compared to the previous year.
- Between 1 April and 7 August 2025, which falls within the winter period, Eskom spent R5.842 billion on fuel for its OCGT plants, generating 988.56GWh of electricity. This output is still higher than the 509.42GWh generated during the same timeframe last year.
- The year-to-date load factor for OCGTs has marginally decreased to 9.35%, reflecting a 0.20% decrease compared to the previous week. This figure remains higher than the 4.82% recorded during the same period last year.
Author: Bryan Groenendaal
Source: Eskom
